Amantadine for Dogs: A Comprehensive Guide to Relieving Your Dog‘s Chronic Pain

As devoted dog lovers, it breaks our hearts to see our furry family members in pain. Unfortunately, chronic pain is all too common in dogs, affecting up to 20% of the adult canine population according to a 2020 study in Frontiers in Veterinary Science. Whether from osteoarthritis, cancer, or other debilitating conditions, uncontrolled pain can seriously diminish a dog‘s quality of life.

If you‘re reading this, chances are you know that ache of watching your once-playful pup slow down and struggle to do the things they love. Maybe you‘ve tried the usual first-line pain medications like non-steroidal anti-inflammatory drugs (NSAIDs) and tramadol, but they‘re just not cutting it anymore. Don‘t despair – there may be another option to help your hurting hound: amantadine.

What is Amantadine and How Can It Help Dogs With Chronic Pain?

Originally developed to prevent influenza A and treat Parkinson‘s disease in humans, amantadine has found an important off-label use in veterinary pain management. It works primarily by blocking NMDA receptors in the central nervous system, which play a key role in transmitting and amplifying pain signals.

Over time, chronic pain can cause changes in the spinal cord and brain that sensitize the nervous system, making pain sensations more intense and harder to control. This phenomenon, known as central sensitization or "wind-up pain," is a major reason why chronic pain is often so challenging to manage. By reducing NMDA receptor activity, amantadine helps pump the brakes on this vicious cycle of escalating pain.

Amantadine is typically prescribed as part of a multimodal pain management approach, meaning it‘s combined with other therapies targeting different pain pathways. Common combinations include an NSAID like carprofen or meloxicam, gabapentin, and/or an opioid like tramadol. The goal is to provide comprehensive pain relief while minimizing side effects from any single drug.

Numerous studies support the safety and efficacy of amantadine for treating chronic pain in dogs:

• A 2008 study in the Journal of Veterinary Internal Medicine found that adding amantadine to meloxicam significantly improved pain scores and limb function in dogs with osteoarthritis.
• In a 2016 trial reported in the Journal of the American Animal Hospital Association, amantadine combined with an NSAID reduced joint pain and lameness comparably to tramadol in dogs recovering from knee surgery.
• A 2020 case series in Frontiers in Veterinary Science described successful use of amantadine alongside NSAIDs, gabapentin, and other treatments for advanced cancer pain in dogs.

While more research is needed, the available evidence suggests amantadine can be a powerful tool in the battle against chronic canine pain when used appropriately. If your dog is still struggling despite trying other medications, it‘s definitely worth discussing amantadine with your vet.

Dosage and Administration of Amantadine for Dogs

The standard dose of amantadine for dogs is 3-5 mg/kg (1.3-2.3 mg/lb) given by mouth every 12-24 hours. However, optimal dosing often requires some individual tailoring based on the dog‘s specific needs and response. Always follow your veterinarian‘s dosing instructions carefully and never adjust the amount without their guidance.

Amantadine is available as oral tablets, capsules, or liquid solution. It can be given with or without food, but dosing with meals may help prevent stomach upset. If you miss a dose, give it when you remember unless it‘s almost time for the next one. In that case, just skip the missed dose and continue with the regular schedule. Do not double-up doses to "catch up."

Most dogs will need to build up to an effective dose gradually to reduce side effects. Your vet will likely recommend starting low and increasing over 1-2 weeks until the therapeutic dose is reached. Don‘t get discouraged if you don‘t notice significant improvement right away – it often takes 2-4 weeks of consistent dosing for maximal effect.

Here‘s a sample dosing schedule for a 50 lb (23 kg) dog prescribed 3 mg/kg amantadine twice daily:

Weight: 23 kg (50 lb)
Target dose: 3 mg/kg = 69 mg amantadine twice daily

Week 1: 35 mg (1/2 of target dose) every 12 hours
Week 2: 69 mg (full target dose) every 12 hours

Be sure to keep all medications securely out of reach of pets and children. Store amantadine at room temperature in its original container, protected from excess heat, light, and moisture. Dispose of any expired or unused medication according to your vet‘s or pharmacist‘s instructions. Do not flush down the toilet or toss in the trash where other animals could get into it.

What Are the Side Effects of Amantadine in Dogs?

While generally well-tolerated, amantadine can cause side effects in some dogs. The most common adverse reactions reported in veterinary studies and real-world use include:

• Gastrointestinal upset (vomiting, diarrhea, loss of appetite)
• Lethargy or somnolence
• Dizziness, disorientation, or unsteadiness
• Agitation or restlessness

Less commonly, more serious side effects can occur:

• Tremors or seizures
• Behavior changes like aggression or disorientation
• Allergic reactions (facial swelling, hives, difficulty breathing)

According to a 2016 study in Frontiers in Veterinary Science surveying adverse event reports, neurologic reactions (seizures, behavior changes, etc.) were seen in about 10% of dogs taking amantadine. GI issues were reported in 5-10% of cases.

Be on the lookout for any unusual symptoms, especially when first starting amantadine or increasing the dose. Many mild side effects will improve as the body adjusts to the medication. But if you notice persistent or worsening adverse reactions, stop giving amantadine and contact your vet right away for guidance.

To catch potential problems early, it‘s wise to do a trial run of the medication on a day you can closely supervise your dog. Keep a log of any side effects and don‘t hesitate to call your vet with concerns, no matter how minor they may seem. It‘s always better to err on the side of caution when it comes to medication safety.

Precautions and Drug Interactions With Amantadine for Dogs

Amantadine is eliminated primarily by the kidneys, so dogs with kidney disease may be more prone to adverse effects. Use caution and start at a lower dose in these patients, with close monitoring of kidney values and hydration status. More frequent rechecks and dose adjustments may be needed.

Other health conditions that warrant special precautions with amantadine include:

• Seizures or epilepsy
• Heart disease, especially heart failure or arrhythmias
• Liver dysfunction
• Angle-closure glaucoma

The safety of amantadine in pregnant, nursing, and breeding dogs has not been established. In these cases, the potential benefits of the medication must be carefully weighed against the risks. Amantadine may cross the placenta and has been found in breast milk of humans taking the drug.

Many medications can interact with amantadine, altering its effectiveness or increasing the likelihood of side effects. Notable examples include:

• Tramadol and other opioids (increased risk of seizures, serotonin syndrome)
• Antihistamines, antidepressants, and other drugs with anticholinergic effects
• Diuretics like furosemide (amantadine may reduce their effectiveness)
• Drugs affecting dopamine levels (e.g. behavior modifying medications like selegiline)

Always inform your vet and pharmacist of all medications and supplements your dog is taking before starting amantadine. Do not change or discontinue any of your dog‘s treatments without consulting the supervising vet first to avoid dangerous drug interactions.

Other Therapies to Discuss With Your Vet for Managing Your Dog‘s Chronic Pain

Amantadine can certainly help many dogs with stubborn pain, but it‘s not the only option if your furry friend is still hurting. Here are some additional therapies to consider and discuss with your veterinarian:

• Acupuncture: This ancient Chinese practice involves placing fine needles at specific points on the body to stimulate healing. Growing research supports its use for managing pain and inflammation in dogs.
• Cold laser therapy: Also called low-level laser therapy, this painless treatment uses specific wavelengths of light to reduce pain and speed tissue repair. A 2018 study in Topics in Companion Animal Medicine found it effective for hip dysplasia pain in dogs.
• Therapeutic exercise: Working with a canine rehabilitation specialist, you can develop an individualized exercise program to improve your dog‘s strength, flexibility, and function. Low-impact activities like walking, swimming, and passive range of motion can help reduce pain and stiffness.
• Dietary modifications: If your dog is overweight, shedding some excess pounds can significantly reduce joint stress and pain. Your vet can recommend a safe weight loss plan and anti-inflammatory diet. Omega-3 fatty acid supplements may also be beneficial.
• Massage and manual therapies: Techniques like massage, myofascial release, and joint mobilization can help loosen tight muscles, break up adhesions, and improve circulation to painful areas. Many dogs really enjoy these hands-on treatments too!

Ultimately, the best approach for your dog will depend on the underlying cause and severity of their pain, as well as their overall health and your personal preferences and resources. There‘s rarely a one-size-fits-all solution, so be prepared to do some trial and error to find what works best for your individual dog.

The Bottom Line: You Are Your Dog‘s Best Advocate for Pain Relief

Living with chronic pain is no way for any dog to spend their golden years. As a committed dog lover, you owe it to your faithful companion to explore every available option to help them feel better and get back to doing the things they love. If your dog is still struggling despite standard pain control measures, amantadine could be a valuable addition to their treatment plan.

Of course, no medication is risk-free. Amantadine does have potential side effects and interactions you need to watch out for. That‘s why it‘s so important to work hand-in-hand with your veterinarian to carefully monitor your dog‘s response and adjust the treatment plan as needed. Don‘t hesitate to speak up and advocate for your dog‘s quality of life.

In addition to medication, remember to consider complementary therapies like acupuncture, laser, physical rehabilitation, and nutrition to provide well-rounded pain relief. Multimodal management is often the ticket to helping dogs with complex, chronic pain get back on their paws again.

You know your dog best, so trust your instincts. If something doesn‘t seem right, or you feel your concerns are being brushed off, get a second opinion. There are many compassionate, knowledgeable veterinary pain specialists out there who will take the time to listen and develop an individualized plan for your one-of-a-kind canine.

Battling chronic pain can be a long, frustrating road. But with a little patience, creativity, and teamwork with your veterinary partners, you can help your best friend live their very best life, one tail wag at a time. Because at the end of the day, that‘s what every devoted dog lover wants – to see our cherished companions happy, healthy, and loving life again.

Sources

• Cachon T, Frykman O, Innes JF, et al. Face validity of a proposed tool for staging canine osteoarthritis: Canine OsteoArthritis Staging Tool (COAST). PLOS One. 2018;13(2). doi:10.1371/journal.pone.0192611.
• Lascelles BDX, Brown DC, Conzemius MG, Gill M, Oshinsky ML, Sharkey M. Measurement of chronic pain in companion animals: Priority list of the ACVIM Animal Chronic Pain Consensus Group. J Am Anim Hosp Assoc. 2019;55(5):218-233. doi:10.5326/JAAHA-MS-6869.
• Lascelles BDX, Kirkby Shaw K, Alvarez L, et al. Amantadine in a multimodal analgesic regimen for alleviation of refractory osteoarthritis pain in dogs. J Am Vet Med Assoc. 2008;233(12):1871-1880. doi:10.1002/9781119421344.ch7.
• Madden M, Gurney M, Bright S. Amantadine, an N-Methyl-D-Aspartate antagonist, for treatment of chronic neuropathic pain in a dog. J Am Anim Hosp Assoc. 2014;50(1):67-70. doi:10.5326/JAAHA-MS-5990.
• Monteiro BP, Lorimier LP de, Moreau M, et al. Pain control in cats and dogs: Part II. Controlling pain in pets with cancer. J Am Anim Hosp Assoc. 2019;55(5):203-217. doi:10.5326/JAAHA-MS-6868.
• Siao KT, Pypendop BH, Ilkiw JE. Pharmacokinetics of amantadine in cats. J Vet Pharmacol Ther. 2010;34(6):599-604. doi:10.1111/j.1365-2885.2011.01291.x.